This invention is directed to a protecting device capable of encasing the locking device of a lever handle door lock to prevent access to the locking device in the lever handle door lock.
In my prior U.S. Pat. Nos. 3,245,240, 4,473,138 and 4,463,584 I respectively disclose protecting devices which are useful for the prevention of ingress and egress to a door having a door knob with a lock integral with the door knob, a protecting device for preventing access to the cylinder lock portion of the padlock and a protecting device for storing keys and the like which fit other locks.
The device disclosed in my U.S. Pat. No. 3,245,240 is very utilitarian in preventing the locking or unlocking of a door knob of the type which incorporates a lock on the door knob. The device disclosed in my U.S. Pat. No. 4,372,138 is very utilitarian in preventing access to the cylinder lock of a padlock or a combination type padlock. Further, the device described and claimed in my U.S. Pat. No. 4,463,584 is very utilitarian in providing a receptacle for storing keys which fit other locks as, for instance, car locks and the like while allowing the use of a single master key to have access to a variety of these storage devices.
While the above protection devices all have utility with respect to particular types of locks, none are usable in association with a lever type door lock. In commercial buildings lever type door locks are increasingly being used. They offer the advantages of being architecturally pleasing as well as providing a secure place for a user of a door to grip while rotating the handle to unlock the door and to pull or push the door to move the door.
In many situations it is desirable to temporarily deny access to the cylinder lock in a common lever handle door lock. By denying access to the cylinder lock, holders of the keys to the cylinder lock are denied access to locking or unlocking the door.